
.main {
    text-align: center;
}
.btn {
    display: inline-block;
    width: 80%;
    text-align: center;
    background-color: rgba(0, 0, 0, 0.6);
    height: 80px;
    line-height: 80px;
    border-radius: 40px;
    margin: 10px;
    color: #fff;
}